Vagcom tweak -- emergency flashing brake lights

**dbonyad** · 25-12-2010,05:51 PM

Hi,

I have a 2009 Audi A4. I have performed many of the Vagcom tweaks available (I have my own kit). Every single one of them works absolutely great, and every change I make is instantly effective.

The only problem I'm having is with the emergency braking tweak. I think this is an important feature for safety reasons but I can't get it to work. In Vagcom I have enabled BOTH the flashing brake light and hazard light activation on heavy braking.

Over the past months there have been a few situations where I've had to perform very heavy (emergency) brakes -- that is as much force to the pedal that I can physically apply. These have been at a variety of speeds.

In none of these situations have the hazard lamps activated (you can see on the mirrors whether they are on). Obviously I can't see the brake lamps but I assume these are constant and not flashing if the hazard lamps aren't activated.

Does anybody know:

Why these are not working? Is there something extra I need to do decide tick the two boxes in the Vagcom software?
Is there a certain speed range where this feature becomes active?

Have any of you managed to get this feature to activate?

Thanks a lot for any advice,
Davood

**ScottyUK** · 26-12-2010,12:10 AM

You're not alone. Many (including me) have activated it without it working

**dbonyad** · 26-12-2010,02:50 AM

I really don't know why Audi don't make this the default mode on cars sold in regions where this is legal.

Has anybody had any success activating this feature? Any ideas on what we could try to enable it?

Thanks

**phil miller** · 26-12-2010,06:02 PM

A while ago i saw a mk6 astra at lights with the brake lights flashing, at the time i thought what a great idea and posted up on here asking if it was poss to do on a mk5, i dont know why you cant get it to work but if you do or someone knows how please post it up as i think it would be a great safety feature

**dbonyad** · 26-12-2010,07:16 PM

I'm not sure about that car but I thought I read that the hardware on the B8 A4 was capable of this.

Anyone?

**MFGF** · 27-12-2010,12:00 PM

Is it worth setting just one of the two options (either hazards OR flashing brakelights) to see if they work in isolation? I'm just wondering whether having both bits set may not be appropriate?

MF.

**kite** · 27-12-2010,12:44 PM

I drove a car with the emergency flashing lights on an experience day.
You would be amazed how hard you had to brake to get the lights to flash
....

**ScottyUK** · 27-12-2010,02:12 PM

When I tested mine the ABS came on on dry roads so I think it was hard enough.

**dbonyad** · 27-12-2010,07:17 PM

I've never tried setting the options in isolation, so I will have a go when I get chance.

Scotty, have you tried this?

With regard to the braking force, it is possible to apply 100% braking force by just pressing the brake pedal as fast and as hard as possible. There is no way to apply a more intensive braking force than this. If that doesn't activate the lights then nothing will.